/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- * * ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is Rhino code, released * May 6, 1999. * * The Initial Developer of the Original Code is * Netscape Communications Corporation. * Portions created by the Initial Developer are Copyright (C) 1997-1999 * the Initial Developer. All Rights Reserved. * * Contributor(s): * Norris Boyd * * Alternatively, the contents of this file may be used under the terms of * the GNU General Public License Version 2 or later (the "GPL"), in which * case the provisions of the GPL are applicable instead of those above. If * you wish to allow use of your version of this file only under the terms of * the GPL and not to allow others to use your version of this file under the * MPL, indicate your decision by deleting the provisions above and replacing * them with the notice and other provisions required by the GPL. If you do * not delete the provisions above, a recipient may use your version of this * file under either the MPL or the GPL. * * ***** END LICENSE BLOCK ***** */ // API class package org.mozilla.javascript; /** * This is interface that all objects in JavaScript must implement. * The interface provides for the management of properties and for * performing conversions. *

* Host system implementors may find it easier to extend the ScriptableObject * class rather than implementing Scriptable when writing host objects. *

* There are many static methods defined in ScriptableObject that perform * the multiple calls to the Scriptable interface needed in order to * manipulate properties in prototype chains. *

* * @see org.mozilla.javascript.ScriptableObject * @author Norris Boyd * @author Nick Thompson * @author Brendan Eich */ public interface Scriptable { /** * Get the name of the set of objects implemented by this Java class. * This corresponds to the [[Class]] operation in ECMA and is used * by Object.prototype.toString() in ECMA.

* See ECMA 8.6.2 and 15.2.4.2. */ public String getClassName(); /** * Value returned from get if the property is not * found. */ public static final Object NOT_FOUND = UniqueTag.NOT_FOUND; /** * Get a named property from the object. * * Looks property up in this object and returns the associated value * if found. Returns NOT_FOUND if not found. * Note that this method is not expected to traverse the prototype * chain. This is different from the ECMA [[Get]] operation. * * Depending on the property selector, the runtime will call * this method or the form of get that takes an * integer: * * * * * * * * * * *
JavaScript codeJava code
a.b a.get("b", a)
a["foo"] a.get("foo", a)
a[3] a.get(3, a)
a["3"] a.get(3, a)
a[3.0] a.get(3, a)
a["3.0"] a.get("3.0", a)
a[1.1] a.get("1.1", a)
a[-4] a.get(-4, a)
*

* The values that may be returned are limited to the following: *

* @param name the name of the property * @param start the object in which the lookup began * @return the value of the property (may be null), or NOT_FOUND * @see org.mozilla.javascript.Context#getUndefinedValue */ public Object get(String name, Scriptable start); /** * Get a property from the object selected by an integral index. * * Identical to get(String, Scriptable) except that * an integral index is used to select the property. * * @param index the numeric index for the property * @param start the object in which the lookup began * @return the value of the property (may be null), or NOT_FOUND * @see org.mozilla.javascript.Scriptable#get(String,Scriptable) */ public Object get(int index, Scriptable start); /** * Indicates whether or not a named property is defined in an object. * * Does not traverse the prototype chain.

* * The property is specified by a String name * as defined for the get method.

* * @param name the name of the property * @param start the object in which the lookup began * @return true if and only if the named property is found in the object * @see org.mozilla.javascript.Scriptable#get(String, Scriptable) * @see org.mozilla.javascript.ScriptableObject#getProperty(Scriptable, String) */ public boolean has(String name, Scriptable start); /** * Indicates whether or not an indexed property is defined in an object. * * Does not traverse the prototype chain.

* * The property is specified by an integral index * as defined for the get method.

* * @param index the numeric index for the property * @param start the object in which the lookup began * @return true if and only if the indexed property is found in the object * @see org.mozilla.javascript.Scriptable#get(int, Scriptable) * @see org.mozilla.javascript.ScriptableObject#getProperty(Scriptable, int) */ public boolean has(int index, Scriptable start); /** * Sets a named property in this object. *

* The property is specified by a string name * as defined for get. *

* The possible values that may be passed in are as defined for * get. A class that implements this method may choose * to ignore calls to set certain properties, in which case those * properties are effectively read-only.

* For properties defined in a prototype chain, * use putProperty in ScriptableObject.

* Note that if a property a is defined in the prototype p * of an object o, then evaluating o.a = 23 will cause * set to be called on the prototype p with * o as the start parameter. * To preserve JavaScript semantics, it is the Scriptable * object's responsibility to modify o.

* This design allows properties to be defined in prototypes and implemented * in terms of getters and setters of Java values without consuming slots * in each instance.

*

* The values that may be set are limited to the following: *

* Arbitrary Java objects may be wrapped in a Scriptable by first calling * Context.toObject. This allows the property of a JavaScript * object to contain an arbitrary Java object as a value.

* Note that has will be called by the runtime first before * set is called to determine in which object the * property is defined. * Note that this method is not expected to traverse the prototype chain, * which is different from the ECMA [[Put]] operation. * @param name the name of the property * @param start the object whose property is being set * @param value value to set the property to * @see org.mozilla.javascript.Scriptable#has(String, Scriptable) * @see org.mozilla.javascript.Scriptable#get(String, Scriptable) * @see org.mozilla.javascript.ScriptableObject#putProperty(Scriptable, String, Object) * @see org.mozilla.javascript.Context#toObject(Object, Scriptable) */ public void put(String name, Scriptable start, Object value); /** * Sets an indexed property in this object. *

* The property is specified by an integral index * as defined for get.

* * Identical to put(String, Scriptable, Object) except that * an integral index is used to select the property. * * @param index the numeric index for the property * @param start the object whose property is being set * @param value value to set the property to * @see org.mozilla.javascript.Scriptable#has(int, Scriptable) * @see org.mozilla.javascript.Scriptable#get(int, Scriptable) * @see org.mozilla.javascript.ScriptableObject#putProperty(Scriptable, int, Object) * @see org.mozilla.javascript.Context#toObject(Object, Scriptable) */ public void put(int index, Scriptable start, Object value); /** * Removes a property from this object. * This operation corresponds to the ECMA [[Delete]] except that * the no result is returned. The runtime will guarantee that this * method is called only if the property exists. After this method * is called, the runtime will call Scriptable.has to see if the * property has been removed in order to determine the boolean * result of the delete operator as defined by ECMA 11.4.1. *

* A property can be made permanent by ignoring calls to remove * it.

* The property is specified by a String name * as defined for get. *

* To delete properties defined in a prototype chain, * see deleteProperty in ScriptableObject. * @param name the identifier for the property * @see org.mozilla.javascript.Scriptable#get(String, Scriptable) * @see org.mozilla.javascript.ScriptableObject#deleteProperty(Scriptable, String) */ public void delete(String name); /** * Removes a property from this object. * * The property is specified by an integral index * as defined for get. *

* To delete properties defined in a prototype chain, * see deleteProperty in ScriptableObject. * * Identical to delete(String) except that * an integral index is used to select the property. * * @param index the numeric index for the property * @see org.mozilla.javascript.Scriptable#get(int, Scriptable) * @see org.mozilla.javascript.ScriptableObject#deleteProperty(Scriptable, int) */ public void delete(int index); /** * Get the prototype of the object. * @return the prototype */ public Scriptable getPrototype(); /** * Set the prototype of the object. * @param prototype the prototype to set */ public void setPrototype(Scriptable prototype); /** * Get the parent scope of the object. * @return the parent scope */ public Scriptable getParentScope(); /** * Set the parent scope of the object. * @param parent the parent scope to set */ public void setParentScope(Scriptable parent); /** * Get an array of property ids. * * Not all property ids need be returned. Those properties * whose ids are not returned are considered non-enumerable. * * @return an array of Objects. Each entry in the array is either * a java.lang.String or a java.lang.Number */ public Object[] getIds(); /** * Get the default value of the object with a given hint. * The hints are String.class for type String, Number.class for type * Number, Scriptable.class for type Object, and Boolean.class for * type Boolean.

* * A hint of null means "no hint". * * See ECMA 8.6.2.6. * * @param hint the type hint * @return the default value */ public Object getDefaultValue(Class hint); /** * The instanceof operator. * *

* The JavaScript code "lhs instanceof rhs" causes rhs.hasInstance(lhs) to * be called. * *

* The return value is implementation dependent so that embedded host objects can * return an appropriate value. See the JS 1.3 language documentation for more * detail. * *

This operator corresponds to the proposed EMCA [[HasInstance]] operator. * * @param instance The value that appeared on the LHS of the instanceof * operator * * @return an implementation dependent value */ public boolean hasInstance(Scriptable instance); }